This invention relates generally to devices and methods for constructing chimney caps.
The chimney cap is a well-known feature found in chimney construction. The chimney cap serves the purpose of preventing moisture from entering the chimney between the chimney liner and the masonry portion of the chimney. This function is important since any water that enters into this space may cause moisture to build up in the masonry work of the chimney and eventually cause spalling and cracking of the masonry if subjected to repeated freezing and thawing, or effloresence on the masonry surface. The cap also serves to keep moisture from pooling on the surface of the top of the chimney and is sloped to keep water out of the flue. The cap is conventionally designed to overhang the chimney body wall. The overhanging portion presents a surface from which water, melting snow or ice can fall free of the chimney body, thus keeping moisture away from the masonry joints in the body.
Chimney caps are typically constructed utilizing wooden forms that are built in place at the top of the chimney. The wooden forms are temporary and are attached to the chimney during final stages of completion. These wooden forms serve as a receptacle for receiving poured concrete or other approved material. In addition, rebar or reinforcing mesh is added to the form so that concrete will not suffer cracking or damage due to shrinkage or thermal expansion that takes place during drying of the concrete or during usage of the chimney.
Standard pour in place chimney cap construction requires that form materials be brought up on the roof and assembled in place at the site to which they are going to be used. Optionally, the form can be constructed on the ground, but this option is problematic because the pre-assembled wood form is heavy and difficult to manipulate and position into place. The involvement of heavy materials and the time inefficient construction of forms is generally inconvenient for the builder of the chimney. Additionally, the manipulation of the form, parts and tools, as well as the heavy material used to construct the form, decreases the margin of safety to the chimney builder. The present invention is directed toward addressing these concerns.